When comparing LightPaper for Mac vs MacDown, the Slant community recommends MacDown for most people. In the question“What are the best Markdown editors for OS X?”MacDown is ranked 6th while LightPaper for Mac is ranked 17th. The most important reason people chose MacDown is:

MacDown is a free and open source editor influenced by [Mou](http://25.io/mou/). It's released under the MIT license.

Pros

Pro

Extended markdown support

Can be extended to support Multimarkdown, GFM-style code fences with syntax highlighting and even math rendering.

Pro

Advanced file-management built-in

Can browse and open files and even has a built-in fuzzy file search.

Pro

Built-in preview

Pro

PDF & HTML export

Pro

Your own preview template is supported

You can create your own template that is aligned with your branding.

Pro

Free and open source

MacDown is a free and open source editor influenced by Mou. It's released under the MIT license.

Pro

Real-time split-screen preview

MacDown's main view is split into two panels. The user types on the left and the Markdown is rendered on the fly in the right panel. This helps users to better understand the way they are formatting their document.

Pro

Good auto-completion

MacDown has a good built-in auto-completion engine for Markdown symbols.

Pro

Markdown previews can be customized with CSS

You can use a CSS file to customize the rendered output and the file preview you are working on will display the rendered Markdown with the custom CSS styling on top.

Pro

Supports syntax highlighting in fenced code blocks

MacDown has syntax highlighting support for various languages when writing code in fenced code blocks.

Pro

Support for GFM

Pro

Ideal for day-to-day programmers' work and MarkDown novices alike

Using MacDown for the notorious README.md use case gets you going without reading any manual or requiring any configuration values. Think of it as a sort of TextEdit for MarkDown files. Thus its shortcomings - neither powerful nor versatile - turn out to be a PRO for novices trying to jump on the MarkDown bandwagon. Open its help and you'll immediately find yourself editing the MacDown's MarkDown help file, a MarkDown primer with some MacDown menus and configuration added.

Cons

Con

Crashed repeatedly and refused to open without crashing after theme installation

Con

Spell checking needs to be activated every time you open a file

In order to activate the spell checker you have to do so every time you open a file in LightPaper. There's no way to leave this setting on by default.

Con

Not very versatile

MacDown is not very powerful or versatile. It's not customizable or extendable. This is what makes it so simple, but it's not for people who want more from their tools.

Con

The Markdown preview is rather heavy on the CPU

The Markdown preview needs a lot of resources to keep rendering on-the-fly after each keystroke. A single keystroke in the editor panel may trigger up to 5 seconds of max-CPU usage.